An apparatus for replacing an abrasive sheet in a sanding machine comprising a working head in which it is provided a support body having an engagement surface arranged to engage with an abrasive sheet. The sanding machine also comprises a handling device arranged to actuate the support body in space according to at least two degrees of freedom. The face of the abrasive sheet facing, in use, towards the support body and the engagement surface of this comprises a mutual engagement means of removable type. For example, the mutual engagement means can provide a layer of Velcro, i.e. a velvet layer on a face and a plurality of hooks on the other face, or an adhesive layer, in particular of reversible glue layer, or a plurality of projections and recesses mutually engageable with each other, or similar engagement elements. Furthermore, is provided a removal station in which it is installed a removal device having a sharp edge arranged to remove the sheet from the support body through a plurality of operations.

An automatic adjustable stroke device for a random orbital machine has a housing with a central axis and a wall defining a cavity. A counterbalance shaft assembly is rotatably disposed at least partially within the cavity. A shaft portion of the counterweight shaft assemblies aligned with the central axis. A mounting assembly is disposed at least partially within the cavity. The mounting assembly has a workpiece attachment mechanism. A stroke adjuster couples the counterweight shaft with the mounting assembly. The stroke adjuster enables the mounting assembly to adjust its stroke upon rotation of counterweight shaft. The mounting assembly variably adjusts a stroke radius of the workpiece attachment mechanism with respect to the central axis of the housing. The stroke adjuster has a gear automatically adjusting the mounting assembly stroke.

An automatic adjustable stroke device for a random orbital machine has a housing with a central axis and a wall defining a cavity. A counterbalance shaft assembly is rotatably disposed at least partially within the cavity. A shaft portion of the counterweight shaft assemblies aligned with the central axis. A mounting assembly is disposed at least partially within the cavity. The mounting assembly has a workpiece attachment mechanism. A stroke adjuster couples the counterweight shaft with the mounting assembly. The stroke adjuster enables the mounting assembly to adjust its stroke upon rotation of counterweight shaft. The mounting assembly variably adjusts a stroke radius of the workpiece attachment mechanism with respect to the central axis of the housing. The stroke adjuster has a gear automatically adjusting the mounting assembly stroke.

The invention refers to a hand-held and hand-guided motor driven polishing or sanding tool (2). The tool (2) has a tool housing (4) and a motor (6; 62) located therein. The tool (2) further has a polishing or sanding working element (8) attached to a tool shaft (10) of the tool (2). The motor (6; 62) is adapted to drive the tool shaft (10) in a first direction of rotation (12).

It is suggested that the tool (2) is equipped with a switch (44) for changing the sense of rotation of the tool shaft (10) between the first direction of rotation (12) and a second direction of rotation (42) opposite to the first direction of rotation (12).

A polishing and/or sanding head (9) comprises: a primary disc (10) which is axially hollow; a rotating shaft (12) which is rotatably received in the internal cavity of the primary disc (10) and designed in such a way as to receive a rotary motion by means of a power take-off external to the head (9); and a body (14) which is radially external and coaxial with respect to the rotating shaft (12); the head (9) also comprises a planetary gear transmission which is adapted to transmit the rotational motion of the rotating shaft (12) to the body (14), and two treatment means (24, 26) which are integral in rotation with the rotating shaft (12) and the body (14), respectively, and have an exposed surface adapted to polish or sand a surface to be treated, which exposed surfaces are rotatable in different directions.

An adjustable stroke mechanism has a housing with a central axis and a wall enclosing a cavity. At least one counterweight is movably disposed within the cavity. A mounting assembly is disposed within the cavity. The mounting assembly has a workpiece attachment mechanism. A stroke adjustor couples the at least one counterweight with the mounting assembly. The stroke adjustor enables the counterweight and mounting assembly to move with respect to one another such that a distance between the counterweight and the mounting assembly is variably adjusted which, in turn, variably adjusts a stroke radius of the workpiece attachment mechanism with respect to the central axis of the housing.

An adjustable stroke mechanism has a housing with a central axis and a wall enclosing a cavity. At least one counterweight is movably disposed within the cavity. A mounting assembly is disposed within the cavity. The mounting assembly has a workpiece attachment mechanism. A stroke adjustor couples the at least one counterweight with the mounting assembly. The stroke adjustor enables the counterweight and mounting assembly to move with respect to one another such that a distance between the counterweight and the mounting assembly is variably adjusted which, in turn, variably adjusts a stroke radius of the workpiece attachment mechanism with respect to the central axis of the housing.

A sanding system is presented that includes a tool with a motor which, when actuated, drives movement of a drive shaft. The system also includes a backup pad coupled to the drive shaft. The backup pad is configured to receive an abrasive article. Movement of the drive shaft causes movement of the abrasive article. The system also includes a compliant damping unit configured to provide variable compliance for the tool when the abrasive article contacting a worksurface. The system also includes an electronic controller that receives a system operating condition and sends a signal to the compliant damping unit based on the system operating condition.

A sanding system is presented that includes a tool with a motor which, when actuated, drives movement of a drive shaft. The system also includes a backup pad coupled to the drive shaft. The backup pad is configured to receive an abrasive article. Movement of the drive shaft causes movement of the abrasive article. The system also includes a compliant damping unit configured to provide variable compliance for the tool when the abrasive article contacting a worksurface. The system also includes an electronic controller that receives a system operating condition and sends a signal to the compliant damping unit based on the system operating condition.

A hand-held/hand-guided random orbital polishing/sanding power tool has a static body and a motor for driving an eccentric element with a rotational movement about a first rotational axis, and a plate-like backing pad rotatably connected to the eccentric element about a second rotational axis. The first/second axes extend parallel to and spaced apart from one another. Part of an external circumferential surface of the eccentric element has a rotational symmetry re the first axis to form a rotationally symmetric part. The tool has a first bearing between the rotationally symmetric part and the static body so the eccentric element is rotatably guided re the static body about the first axis, and also having a mechanical gear arrangement with two meshing gear wheels arranged between the motor's drive shaft and the eccentric element, and one meshing gear wheel attached to the eccentric element for transmitting torque thereto.